Wow, thanks for all the info, Zoebird. I'd read somewhere before that shoes alter the natural gait. I always had problems with shoes as a kid. My Mom would try to buy orthopedic shoes for me because, as she would tell the shoe salespeople, "She walks funny".
I scoped out a local trail today, and I think I can manage most of it barefoot. I'll take my water shoes with me for the parts with small rocks. I have to wear closed-toe shoes for part of my job (lab and greenhouse), but other than that, I think I'll be using my sandals or flip-flops the rest of the summer.